Judd told HuffPost UK all the children in the video are “confirmed cases of infantile spasms being treated in hospital by neurologist”.

Ley Sander, medical director at Epilepsy Society and professor of neurology at University College London, said that although he cannot comment on individual cases as babies have to undergo a range of tests before they can be officially diagnosed with infantile spasms, it does appear as though the babies in the video are showing signs of having the syndrome.

“Infantile spasms most commonly begin in the first nine months of life,” he told HuffPost UK.

“They can often affect children who have had a brain injury before the age of six months. Spasms or jerks come in clusters and can affect the whole body or just the arms and legs. Each cluster can include up to 100 individual spasms which often happen as the child is waking up.

“Studies are currently looking at treating this syndrome with anti-epileptic drugs and steroids, although 25% of children with spasms do not respond well to treatment. We do know however, that the earlier a child is treated, the better the outcome.”

Chantal Spittles, of Epilepsy Action, added: “The attacks are usually brief and infrequent and therefore it’s quite common for the diagnosis to be made late.

“If a baby is having a spasm, their body, arms and legs usually stiffen and bend forwards. It is common for babies having infantile spasms to become irritable and for their development to slow or go backwards until their spasms are controlled.”

Epilepsy Action’s advice is that if you suspect your child is having any kind of spasms as shown in the video above, seek medical advice as soon as possible as: “the sooner any potential epilepsy can be diagnosed and treated, the better”.

Professor Sander agreed: “If you suspect your child is having spasms, it is important to seek medical advice from your doctor. It is also useful to video the spasms on your phone as this can be very useful in diagnosis.”

The video has been viewed nearly 15,000 times in four days.

“Thank you for sharing your story and putting awareness out,” one person wrote.

Another commented: “Great video and so important to share. We could easily have missed our little girl’s spasms at five months and written them off as normal jerky baby movement.”

Symptoms of infantile spasms:

The typical pattern is of a sudden flexion (bending forward) in a tonic (stiffening) fashion of the body, arms and legs.

Sometimes, the episodes are different, with the arms and legs being flung outwards (these are called ‘extensor’ spasms). Usually, they affect both sides of the body equally.